Playing in the NFL is one of the most physically demanding sports. The players are exposed to many hard hits and are often injured. This plus given the fact the NFL is highly competitive, and there is a large group of talented players wanting to take the place of those who are injured or no longer able to perform at a high level, most careers are not long. The average length of a player's career in the National Football League is relatively short compared to other sports. One study shows the average career lasts around 3.3 years.[1] Kickers and punters careers average 4.87 seasons.[1] On the other end, the shortest average careers are the running backs, only 2.57 seasons.[1] According to data compiled by another study,[2] quarterbacks and offensive linemen are next on the list with average career spans of 4.44 and 3.63 seasons, respectively. Defensive linemen usually have longer careers than linebackers and cornerbacks. Wide receivers careers average just above running backs at 2.81 seasons[2]
Some players avoid injury and maintain their high skill level. The following list has the top 250 players who have the most regular season game appearances. All have played at least a dozen seasons in the league. One player, George Blanda[3] played in 4 decades from the 1940s to the 1970s. Blanda played 26 seasons and was 48 years when he retired.